左连接
var LeftJoin = from emp in ListOfEmployees
join dept in ListOfDepartment on emp.DeptID equals dept.ID into JoinedEmpDept
from dept in JoinedEmpDept.DefaultIfEmpty()
select new {
EmployeeName = emp.Name,
DepartmentName = dept != null ? dept.Name : null
};
右连接
var RightJoin = from dept in ListOfDepartment
join employee in ListOfEmployees on dept.ID equals employee.DeptID
into joinDeptEmp from employee in joinDeptEmp.DefaultIfEmpty()
select new {
EmployeeName = employee != null ? employee.Name : null,
DepartmentName = dept.Name
};
内连接
var query = from t in entitiy.TB_GCGL_ADA_USER
join p in entitiy.TB_GCGL_ZY_ZYK on t.ETPRS_CODE equals p.ETPRS_CODE
select new TB_USER_ZYK {
USER_ID = t.USER_ID,
USER_NAME = t.USER_NAME,
USER_PASSWORD = t.USER_PASSWORD,
};